The invention discloses a high-titanium and low-cost Q345B hot-rolled acid washing plate and a production method thereof, and mainly solves such problems as higher production cost, low yield, weak formability and weak welding performance of Q345B hot-rolled acid washing plates produced in the prior art. The high-titanium and low-cost Q345B hot-rolled acid washing plate, provided by the invention, consists of the following components in percentage by weight: 0.12-0.16% of C, Si not more than 0.35%, 0.10-0.50% of Mn, P not more than 0.020%, S not more than 0.015%, 0.015-0.040% of Als, 0.045-0.070% of Ti, N not more than 0.006%, and the balance of iron and inevitable impurities. The invention further provides the production method; and the production method comprises the following steps: a hot-rolled acid washing plate continuous casting blank is prepared according to all the components and the weight percentages thereof; the winding is performed after heating insulation, high-pressure water descaling, rough rolling, finish rolling and laminar cooling; and finally, the Q345B hot-rolled acid washing plate with performances satisfying the GB/T1591-2008 requirements is produced. The high-titanium and low-cost Q345B hot-rolled acid washing plate realizes large reduction of the production cost, effectively reduces banded structures and manganese sulfide inclusions, reduces the sensitivity of cracks at corners of the casting blank, and effectively prevents generation of such defects as skin upwarp.